Global investment in clean energy totaled $56.6 billion in the third quarter, some 20 percent lower than the same period last year thanks partly to a lull in wind farm financing and weaker performance from the United States and India, according to the latest report from Bloomberg New Energy Finance.

The figures don't just illustrate the rather tepid investment environment, they also hint at a slightly bleaker future. BNEF says the figures suggest the full-year of 2012 for investment in clean energy is likely to fall short of last year's record $280 billion. If so, 2012 would be the first down year for world investment in the sector for at least eight years, the research company said.

The big challenges clean energy faced in the third quarter are really just a continuation of ongoing hurdles and hiccups. Policy uncertainty in key markets such as the U.S., the U.K. and Italy was the big wet blanket. The recent falls in the costs of wind and solar photovoltaic technologies have meant that the same megawatt capacity can now be purchased for significantly fewer dollars, making it harder to make a profit.

This gloomier outlook doesn't necessarily mean the industry is headed for a death spiral. The third quarter figure was still well over $50 billion, roughly equivalent to investment in the whole of 2004, said BNEF CEO Michael Liebreich.

Kirsten Korosec has written for Technology Review, Marketing News, The Hill, BNET and Bloomberg News. She holds a degree from Northwestern University's Medill School of Journalism. She is based in Tucson, Arizona.
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